Mozilla is focusing a lot of its efforts towards important web and mobile projects, while Thunderbird remains a pure desktop only email client. We have come to the conclusion that continued innovation on Thunderbird is not a priority for Mozilla and that the most critical needs for the product are on-going security and stability. In fact, it is quite possible that Thunderbird is already pretty much what its users want and there is not a high demand for innovation in this field.

However, we do recognize that there is a very large number of users (more than 20 million) who use Thunderbird and rely on it on a daily basis, sometimes for the most mission critical tasks. Furthermore, Thunderbird is one of the very few truly free and open source multi-platform email application available today and we want to defend these values.

In order to manage these two perspectives, we are proposing to adapt the Thunderbird release and governance model in a way that allows both ongoing security and stability maintenance as well as community driven innovations for the product. We are opening this plan for discussion to individuals and organizations interested in maintaining and advancing Thunderbird in the future. We are looking for your feedback, comments and suggestions to refine and adapt the plan in the best possible way.

Summary

Thunderbird and Thunderbird ESR

There are currently two editions of Thunderbird: 'Thunderbird' and 'Thunderbird ESR'. Both will be maintained and based on the same Gecko engine release. Only 'Thunderbird' is affected by the change:

• A new release of Thunderbird ESR is available since November 20th, 2012. As defined in the Thunderbird ESR plan, it has inherited the then-current Thunderbird feature-set. This release will be updated every six weeks, for the duration of the ESR cycle to ensure the best possible security and stability for organizations.
• At the same time, Thunderbird has been released with the same feature set as Thunderbird ESR and will be updated every six-weeks for security and stability. However, and contrary to Thunderbird ESR, Thunderbird may include an additional release during the ESR timeframe which would include extra features.

The plan should therefore have no impact in the way individuals and organizations use the product and obtain updates.

Governance model

Thunderbird is driven by a lightweight structure, focusing on producing security updates and suited to welcome community contributed innovations:

• Thunderbird modules owners remain in charge of their module and allow community contributions innovation on their own merits. Module ownership is open to any contributor and can evolve over time.

• The Release Drivers team produces the Thunderbird updates every six weeks and works with module owners on the planning and integration of the community contributed innovations.

• Mozilla continues to provide paid staff, logistics and infrastructure for the release drivers team to produce updates and new releases with the same level of quality than today. Support continues to be provided by the Thunderbird community and Mozilla continues to provide the required infrastructure.

Governance

As we move forward there will be two teams responsible for the governance of Thunderbird; Module Owners and Release Drivers.

Module Owners

Module Owners are responsible for welcoming contributions and ensuring that related changes that are applied to Thunderbird's code base are in line with Mozilla's values and the Thunderbird Brand, and ensuring the quality and standards of the code via the normal methods of code review and unit testing. This list also applies to the sub-module owners and peers. In addition to code modules, there are 3 virtual sub-modules handling the following:

• Engagement: activities such as product communications, community members meetups, promotional items re-ordering & relationship with MozGear group...
• Business Development (BD): in-product partners inclusion & revenues, licensing...
• User Experience (UX): across modules User Experience consistency

The list of module owners will change over time. This should generally be in accordance with the rules for Module Owners and Peers

Roadmaps

Anyone can contribute or suggest directions or features to Thunderbird, these may be discussed with the community and modules owners. If there is conflict, then the module owners will have the final decision on inclusion in the product.

There are no defined roadmaps for Thunderbird, although module owners and the community may suggest areas of focus.

Features are contributed when ready and will be included in the next release. Prior discussion is encouraged for large features.

Release Drivers

Release Drivers are responsible for ensuring:

• that releases are produced at the required times, with appropriate support for QA, websites, etc
• the security of the product
• new features have met the requirements for reviews including security and privacy reviews

The Release Driver operations cover:

• Release Management *
• Release Engineering
• Security & Privacy *
• Localisation
• Support
• QA *
• Documentation
• Business Development & Legal *
• Marketing & Engagement *
• Web Development

The functions marked with a * are ones that must to be vetoed/reviewed by Mozilla-paid staff to ensure that the brand requirements are met.

The release drivers functions may be supplemented and additionally advised by community members.

The release drivers mailing list is restricted due to the nature of discussions that take place, for example, about security issues that affect releases.

Revenues and use of money

Thunderbird revenues are composed of revenues generated by product externalities and/or donations. Money generated by externalities are to be used solely for engagement purposes. Money generated by donations is to be used for engagement or other purposes. Donations are for general purposes. They do not grant the donator any rights whatsoever to the product nor are they made specifically for a specific work such as feature development. The module owners group at large decides by consensus money spending community propositions.

Paid-for development will be very difficult to handle acceptably for the community and will have far reaching governance leadership implications. Therefore, paid-for development should not be considered. Instead, contributions of development resources should be encouraged.

Resources provided by Mozilla

Mozilla provides the following resources for Thunderbird:

The Thunderbird release driver team is composed of the following paid-staff:

• Lead Engineer & Release Driver: Mark Banner
• Back End Integration Engineer: Irving Reid
• Quality Assurance: Ludovic Hirlimann
• Web Development: Andrei 'Sancus' Hajdukewycz
• Support: Roland Tanglao
• Release Engineering: John Hopkins
• Business Development & Legal: Jean-Baptiste Piacentino

Infrastructure to build and support Thunderbird remains untouched (Release Engineering, Web Services and Support services).

Releases

• From Thunderbird 17, releases will generally follow the ESR branch.
• There will be one or two feature releases per year; the first of these in sync with a new ESR branch, the second is an optional release.
• There will be security releases every 6 weeks of both mainstream and ESR.
• Mainstream and ESR releases will not be merged to allow for the intermediate release.
• We will examine the possibilities for relaxing the rules for stability and security fixes on the ESR branch to allow a greater range of fixes to be landed.
• Daily, Earlybird and Beta channels will continue to be developed
  • this will continue to provide the platforms for helping ensure stability for the next feature release and
  • for Localizers to translate the required strings
• Releases on the beta channel will be reduced to one per gecko cycle
  • An additional release may happen if a severe (stability/security) issue affecting beta users is found
  • Additional releases will happen in the two cycles in the run-up to the next feature release to help to ensure stability

Although the intermediate release is not desired at the current time, for an intermediate release to happen, the following would be required:

• A set of features / improvements that can't be incorporated into the normal stability / security releases, due to breaking add-on compatibility or changing localized strings
• Community commitment to back-port the features
• A way for the localization of the strings to be back-ported

The decision for the intermediate release is made by the module owners, but signed off by the release drivers.

Localization

• In-product l10n:
  • Due to the release pattern, localizers can continue to work as the have been with the rapid release
  • If an intermediate release is held, we would need to work out how to back-port sign-offs and changes to an intermediate release branch
  • Currently there are no plans to allow localizers to do updates on the ESR branch, but this is open to feedback and may change
• Website L10n:
  • This should remain the same process as it is now, unless mozilla.org policies change

AMO

• Add-on Review mechanisms to continue working as they are with the AMO editor team
• Compatibility bumps still need to be done per release (partial documentation complete)

Quality Assurance

• Ludovic will continue to lead and head up QA
• This is already a community-involved process
• Todo: Document how bugs get from triage to developers

Services & Web Sites

• Generally, services will continue to have hardware supported by Mozilla IT.
• mozilla.org site style maintained by Mozilla Web dev team, content updates by community and release drivers team.
• support.mozillamessaging.com is expected to be integrated into support.mozilla.org.
• ispdb expected to be brought up to replace the static files for autoconfig.
• Other sites expected to be low maintenance, but change processes to be documented.

Support

• Support sites are already largely community supported and driven
• support.mozillamessaging.com will continue until SUMO integrates Thunderbird KB in to the support.mozilla.org KB (currently scheduled for late Q4 as part of multi-platform work for Firefox OS and Firefox Mobile to be confirmed in early to mid Q4)
• get satisfaction continues as Thunderbird support forum until SUMO integrates Thunderbird forums into the support.mozilla.org forums (currently scheduled in Q1 as part of multi-platform work for Firefox Mobile, to be confirmed in mid to late Q4)
• Add-on support is status-quo - there's not much we can do in the KB. In Get Satisfaction it is suggested the use of an add-on specific tag e.g. 'conversations' for Thunderbird Conversations add-on, 'lightning' for Lightning, etc. - this really to me is an AMO issue but happy to use tags on GS until AMO has a better support experience for add-ons
• Roland continues to lead support
  • Will still produce support reports 48 hours after release and the Monday after a release

Docs

• Documentation will continue to be on support.mozillamessaging.com, or support.mozilla.org as mentioned in the support section
• Documentation has good community involvement already, contact via the support mailing list
• Need to ensure that the necessary documentation for releases is co-ordinated with release drivers

Engagement

• Engagement will be taken care of by a contributor. A Mozilla Reps is identified
• it will cover the maintenance of current Facebook and Twitter accounts, opening new channels if needed
• being a virtual module owner
• managing eventual contributors event logistics
• updating Start Page editorial calendar twice a year
• liaising with MozGear for swags allocation to Friend of the Tree
• keeping the Mozilla brand usage in line within Mozilla guidelines

Lightning

• Lightning will suffer from less manpower, specifically with Build Config and UI Design
• Lightning's pace of development won't be significantly affected by this change
• There may be a benefit during upgrades, as fewer binary-compatibility issues will arise.
• Daily/Earlybird builds have to be monitored more closely, as they are the only notice for major platform changes that might affect Lightning.

Other Resources

This document was originally discussed, on a proposed version that can be found here.